1. Field of the Invention
The present invention relates to a light-sensitive material processing apparatus for processing an imagewise exposed light-sensitive material while the light-sensitive material is being conveyed to a plurality of processing tanks accommodating a processing solution.
2. Description of the Related Art
A light-sensitive material on which an image has been exposed, e.g., a presensitized printing plate for planographic process, is transported into a presensitized printing plate processor, which is a light-sensitive material processing apparatus, and is subjected to development in a developing tank provided in the presensitized printing plate processor, and is then washed in a rinsing tank or a washing tank before a finisher, i.e., a finishing solution, is applied thereto.
A developer in a processing tank for processing the light-sensitive material, such as the developing tank, undergoes variations in its concentration due to evaporation as well as deterioration due to processing. For this reason, the quantity of replenisher is set in accordance with the detected result of the electrical conductivity of the developer as well as the number of films processed so as to effect replenishment.
In other words, since the concentration of the developer becomes high owing to the evaporation of water contained in the developer, water is replenished in correspondence with the detected result of the electrical conductivity of the developer. In addition, both the concentrated developer and water are supplied in correspondence with the areas of the light-sensitive material processed so as to maintain the activity of the developer.
However, with the light-sensitive material processing apparatus having a plurality of processing tanks (e.g., a first developing tank, a second developing tank, and a finisher tank), it is necessary to provide a conductivity detector for each processing tank for development in order to detect the electrical conductivity of the processing solution in each processing tank. Hence, there have been problems in that this disadvantageously results in higher cost and that the maintenance operation for each of these conductivity detectors is troublesome.
In addition, it is conceivable to provide the conductivity detector only for the developing tank for which the variations in concentration are large among the plurality of developing tanks, and to replenish the aqueous solution only for that developing tank. Nevertheless, since the concentration of the developer in the other processing tanks becomes high, development residue produced from the light-sensitive material is not dissolved in the developer in the developing tanks and becomes solidified in the developing tanks. In addition, the concentration becomes high in the other processing tanks as well, resulting in faulty processing. Hence, there arises the problem that it is impossible to effect development on a stable basis over extended periods of time.